Plumbing hub



FIG. 1 shows a top front perspective view of a plumbing hub.

FIG. 2 shows a top, rear perspective view of the plumbing hub.

FIG. 3 shows a front elevation view of the plumbing hub.

FIG. 4 shows a side elevational view of the plumbing hub; and,

FIG. 5 shows a top elevation view of the plumbing hub.

The broken lines represent unclaimed portions unclaimed portions of the plumbing hub and form no part of the claimed design. 

CLAIM We claim the ornamental design for a plumbing hub, as shown and described. 